Pod People

They’re the ones thinking outside the space capsule.

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So much for IMP. Scientists soon found another way to get micrometeoroid detectors into space—on test flights of Saturn boosters. But the idea of inflatable reentry vehicles had caught the imagination of engineers, including some outside NASA, who started musing about light craft that could make the return trip all the way from Earth orbit. “We did nothing intentional to inspire it,” Kinard says, “but we got lots of attention.”

One of those engineers was Robert Brodsky, who at the time was in charge of bringing in work to Aerojet-General’s Space General division, which had built the Aerobee rocket. Aerojet had designed the electronics and other systems for IMP, while B.F. Goodrich had built the structure. Even before IMP’s test flight, both companies started pushing the concept of inflatable reentry with their customers, primarily the Department of Defense. In the early 1960s, the Pentagon was flirting with developing its own astronaut program (see “A Sudden Loss of Altitude,” June/July 1998) and was interested in proposals for a small, storable craft that could return a person from orbit in a hurry.

“I got the idea that we could alter the IMP design sufficiently to turn it into a space lifeboat,” Brodsky says. He saw it as an option for dire emergencies only, like a life raft on an oceanliner.

“There were only two reactions,” Brodsky recalls. “Initially, sheer incredulity.

Then—seeing the challenge—great enthusiasm.” In 1962 the Air Force materials lab gave his company $250,000 to look into the concept; the funding later grew to $1 million. “In those days, that was a lot of money,” he says.

The project lead was Jesse (“Bud”) Keville, a 37-year-old engineer who set to work designing the lifeboat and building and testing components. Space General called it Project FIRST, for “Fabrication of Inflatable Reentry Structures for Test.” Keville’s team kept the basic IMP paraglider with its three inflatable struts, and placed a prone astronaut in the center strut. The lifeboat weighed a mere 850 pounds. Stowed on a spacecraft, it could fit in a threefoot by 10-foot cylinder; inflated, it was 23 feet long, with a wingspan of 28 feet. The engineers even came up with a deluxe three-person version, and a six-person model that weighed a ton.

The inflatable wing spars were made of nickel-chromium alloy mesh. For thermal protection, the mesh was saturated with liquid silicone and covered with another layer of silicone rubber. A vehicle returning from orbit would experience more heating than IMP had during its suborbital flight, and vacuum chamber tests showed that this material could handle temperatures of more than 2,000 degrees Fahrenheit. The wing material, says Keville, “resembled a lightweight burlap.” At first he had trouble finding a textile company that could handle the tricky job of weaving metal yarn, but he finally found one called Prodesco, in Perkasie, Pennsylvania. Keville spent weeks in the small town, which had “only one general store and a Quaker church.”

The FIRST lifeboat was designed to be folded up in a small container on the outside of a spacecraft. An astronaut abandoning ship would enter the pod through a small hatch leading to the outside. After inflating the paraglider with nitrogen fed through a hose or from gas bottles, the escapee would fire solid rockets in the central spar to deorbit the craft. The fall from orbit (400,000 feet) down to 120,000 feet would take half an hour, with attitude control jets used for maneuvering. Once it became aerodynamic in the lower atmosphere, the paraglider could be steered by changing the pressure within the inflatable spars to achieve a kind of wing-warping. The landing would take place anywhere within a footprint 450 miles wide and 1,400 miles long.

Five years of research convinced the FIRST engineers that the concept was feasible. Unfortunately, by the late 1960s it was no longer wanted. Neither Apollo nor Skylab, NASA’s first space station, were in the market for a bailout system, and the Department of Defense was already starting to back away from plans for its own station. Inflatable lifeboats had become the answer to a question no one was asking.

From the beginning, Brodsky had had grander things in mind for FIRST, based on futuristic schemes that Wernher von Braun and others were espousing at the time. “[FIRST] was begun to meet an apparent need for a wheel-like rotating space station,” he says. “It was terminated when it was apparent that we were too early. The idea of a [large] manned space station was no longer in vogue.”

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